I guess I feel you could get used to anything, if you were forced to use it enough... however, if you own more than one gun, & one feels great in your hand, & one feels "un-natural" you're likely to never shoot the ill fitting gun enough for it to feel natural... you'll just take the one that fits better to do the bulk of your shooting...

however if you were limited to one gun, & forced to use it, you may find you conform to the gun & get "used to it" though it may never perform at the same level as if you started with a nice fitting gun & were "forced to use it"